Initial commit: PaperScan — lokale Android documentscanner voor Paperless-ngx

Native Kotlin/Compose app met CameraX + OpenCV randdetectie/perspectiefcorrectie,
multi-page PDF-export, en Paperless-ngx upload (of Android deelmenu). Alles lokaal.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitea/workflows/build.yml

@@ -0,0 +1,46 @@
+name: Build APK
+
+# Bouwt een getekende release-APK op elke versietag (v0.1.0, …) en op handmatige trigger.
+on:
+  push:
+    tags:
+      - "v*"
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    # Image met Android SDK + JDK 17 + Gradle voorgeïnstalleerd.
+    container:
+      image: mingc/android-build-box:latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Herstel signing keystore uit secret
+        run: |
+          echo "$SIGNING_KEYSTORE_BASE64" | base64 -d > "$GITHUB_WORKSPACE/release.jks"
+        env:
+          SIGNING_KEYSTORE_BASE64: ${{ secrets.SIGNING_KEYSTORE_BASE64 }}
+
+      - name: Genereer Gradle wrapper indien nodig
+        run: |
+          if [ ! -f gradle/wrapper/gradle-wrapper.jar ]; then
+            gradle wrapper --gradle-version 8.11.1
+          fi
+
+      - name: Build release APK
+        run: |
+          chmod +x ./gradlew
+          ./gradlew --no-daemon assembleRelease
+        env:
+          SIGNING_STORE_FILE: ${{ github.workspace }}/release.jks
+          SIGNING_STORE_PASSWORD: ${{ secrets.SIGNING_STORE_PASSWORD }}
+          SIGNING_KEY_ALIAS: ${{ secrets.SIGNING_KEY_ALIAS }}
+          SIGNING_KEY_PASSWORD: ${{ secrets.SIGNING_KEY_PASSWORD }}
+
+      - name: Upload APK als artifact
+        uses: actions/upload-artifact@v3
+        with:
+          name: paperscan-release
+          path: app/build/outputs/apk/release/*.apk